1. Field of the Invention
The present invention relates to a wireless apparatus, and more particularly, to a wireless apparatus having a shielding function for shielding signal interference between driving power from a power amplifier and a conductive wire of a coupler.
2. Description of the Related Art
In general, electronic devices, employing wireless communications circuits, are in wide use since they are easy to use and carry and are advantageous in terms of installation and maintenance.
Representative examples of electronic devices employing wireless communications circuits include mobile communications terminals, personal digital assistants (PDA) and the like.
Such wireless electronic communications devices use a transceiver circuit for transmitting and receiving a signal that contains information.
The transceiver circuit includes a power amplifier that amplifies the power of a received signal or a signal, which is to be transmitted.
The output signal of the power amplifier is transmitted to an antenna or a receiving circuit after experiencing power coupling and impedance matching. The harmonic level of the output signal from the power amplifier is required to be at least −10 dB or less.
The power amplifier and a power coupling circuit, the essential components of the transceiver circuit, are integrated onto a single board. In this case, the power amplifier may be formed by using a complementary metal oxide semiconductor (CMOS) process, and the power coupling circuit may be formed by using an integrated passive device (IPD) process.
In the above-described configuration, the power line of an external driving power source is installed above a power coupler. For this reason, the harmonic levels, and the second-harmonic levels in particular, are deteriorated, which leads to failure to meet consumer demand.